Creating grid lines with photoshop is easy, and can be used to make your imagery look tight and froody.
STEP 1.
Go into the channels window and create a new channel. Make a square selection about 20 pixels wide with the marquee tool. Fill it with white.
STEP 2.
In the menu, go:SELECT > MODIFY > CONTRACT > Contract by: 1 pixel
Then, fill the selection with black. It will now look like a small white outlined box.
STEP 3.
With the Marquee tool still selected, nudge the selection up and to the left, 1 pixel.
In the menu, go:
EDIT > Define Pattern
STEP 4.
Clear the selection (Ctrl-D) and create a new channel.
Open the Paint Bucket options window and set the contents to PATTERN
Fill the new channel by clicking with the paint bucket tool, and a grid texture will magically appear.
STEP 5.
Drag the grid channel onto the "Load channel as selection" button. [
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Go to the layer window. Create a new layer and fill the selection. (Alt-Backspace)
STEP 6.
Enjoy the attractive imagery you and your new-found skills have just created and celebrate over a steaming bowl of re-digested monkey-brains.
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